Next-generation fitness sensors could give deeper insights into human health through noninvasive testing of bodily fluids.
Next-generation fitness sensors could give deeper insights into human health through noninvasive testing of bodily fluids. A stretchy patch developed at KAUST could help this approach by making it easier to analyze sweat for critical biomarkers.
Human perspiration contains trace amounts of organic molecules that can act as measurable health indicators—glucose fluctuations, for example, may point to blood sugar problems, while high levels of lactic acid could signal oxygen deficiencies. To detect these molecules, researchers are developing flexible prototypes that sit on the skin and direct sweat toward special enzyme-coated electrodes. The specific nature of enzyme-substrate binding enables these sensors to electrically detect very low concentrations of target compounds.
One obstacle with enzyme biosensors, however, is their relatively short lifetimes. “Even though human skin is quite soft, it can delaminate the enzyme layer right off the biosensor,” says Yongjiu Lei, a Ph.D. student at KAUST.
Image: A schematic diagram of the sensor system showing how the drops of sweat are directed towards the electrodes that are coated with enzymes that can detect low concentrations of target compounds. (Credit: Reproduced with permission from reference 1 © 2019 John Wiley & Sons)